Medieval and early modern texts:

The texts in this section are English translations or transcriptions unless otherwise noted
(I hope). I have listed them in three groups, alphabetically arranged:
the first, for works with named authors arranged by surname (or place name)
if any, otherwise by Christian name;
the second for anonymous works arranged by place name;
and the third for anonymous works arranged by subject matter.

A Victorian catalogue of medieval sources is itself available online:

Thomas Duffus Hardy,
Descriptive catalogue of materials relating to the history of Great Britain and Ireland, to the end of the reign of Henry VII
(gallica;
Bibliothèque Nationale de France; numbers for "Recherche libre" field: N050191-4)
PDF format (Rolls Series 26, vols 1-3 (in 4 parts); 1862-1871)

Extracts from Peter of Blois
on
William Rufus and
Henry I
(John Jay Phillips, Conquest)
[not available, 19 April 2015; see the Internet Archive's
copy of this page, from September 2013]
English translations, from Henry T. Riley,
Ingulf's Chronicle of the Abbey of Croyland
with the Continuation of Peter of Blois (1854)

Robert Blondel, De reductione Normandiae,
in Narratives of the expulsion of the English from Normandy, M.CCCC.XLIX.-M.CCCC.L [1449-1450]
(gallica;
Bibliothèque Nationale de France; number for "Recherche libre" field: N050232)
PDF format; Latin text from the edition of the Rev. Joseph Stevenson
(Rolls Series 32; 1863)

William Stewart,
The buik of the croniclis of Scotland, or a metrical version of the History of Hector Boece
(gallica; Bibliothèque Nationale de
France; numbers for "Recherche libre" field: N050150, N050152)
PDF format; text (incomplete) from the edition of William B. Turnbull (Rolls Series 6, vols 1 and 3; 1858)

Gilles le Bouvier ("Berry"),
Le Recouvrement de Normandie,
in Narratives of the expulsion of the English from Normandy, M.CCCC.XLIX.-M.CCCC.L [1449-1450]
(gallica;
Bibliothèque Nationale de France; number for "Recherche libre" field: N050232)
PDF format; Latin text from the edition of the Rev. Joseph Stevenson
(Rolls Series 32; 1863)

De Legibus Et Consuetudinibus Angliæ (On the Laws and Customs of England) (Cornell Law School and collaborators)Latin text of George Woodbine, and English translation by S. E. Thorne.

Jocelin of Brakelond,
Chronicle of the Abbey of St Edmund's (1173-1202)
(Internet Medieval Sourcebook, Fordham University)
English translation from L.C. Jane, ed.,
The Chronicle of Jocelin of Brakelond Monk of St. Edmundsbury:
A Picture of Monastic and Social Life on the XIIth Century (1907)

John of Bridlington,
in Political poems and songs relating to English history,
composed during the period from the accession of Edw. III to that of Ric. III
(gallica;
Bibliothèque Nationale de France; numbers for "Recherche libre" field: N050165, N050166)
PDF format; texts - in various languages - from the edition of Thomas Wright
(Rolls Series 14, vols 1 and 2; 1859-1861)

Gervase of Canterbury,
The historical works of Gervase of Canterbury
(gallica; Bibliothèque Nationale de
France; number for "Recherche libre" field: N050339)
PDF format; Latin text (incomplete) from the edition of William Stubbs
(Rolls Series 73, vol.1 (of 2); 1879)

Philippe
de Commynes,
The Reign of Louis XI 1461-83 (in progress; Richard III Society - American Branch: On Line Library – Text and Essays)
Extracts from Books 1-6; from the English translation by Michael Jones (1967)

Reginald of Durham,
Life of St. Goderic [12th Cent]
(Internet Medieval Sourcebook, Fordham University)
English translation from
G.G. Coulton, ed., Social Life in Britain from the Conquest to
the Reformation (1918)

Thomas of Eccleston,
De adventu fratrum minorum in Angliam,
in Monumenta franciscana
(gallica; Bibliothèque Nationale de
France; numbers for "Recherche libre" field: N050147, N050148)
PDF format; Latin texts from the edition of J. S. Brewer
and Richard Howlett (Rolls Series 4, vols 1 and 2; 1858, 1882)
(Also available at the Medieval
and Modern Thought Text Digitization Project, Stanford University,
as a very large (37 MB) PDF file)

The Chronicles of Froissart
(Electronic Text Center, University of Virginia)
Extracts from the 16th-century English translation by John Bourchier, Lord Berners,
from the edition of G.C. Macaulay (1910)

John Gower, several poems,
in Political poems and songs relating to English history,
composed during the period from the accession of Edw. III to that of Ric. III
(gallica;
Bibliothèque Nationale de France; numbers for "Recherche libre" field: N050165, N050166)
PDF format; texts - in various languages - from the edition of Thomas Wright
(Rolls Series 14, vols 1 and 2; 1859-1861)

Edward Grim,
The Murder of Thomas Becket
(Internet Medieval Sourcebook, Fordham University)
English translation by Dawn Marie Hayes,
from the text published in James Robertson, ed.,
Materials for the History of Thomas Becket
(Rolls Series 67; 1875-1885)

Robert Grosseteste: [Bishop of Lincoln, d.1253] Letters

Letters (the Electronic Grosseteste, University of Leeds)Latin texts of 130 letters, from the edition of Henry Richards Luard (Rolls Series 25; 1861). The same site also contains texts of Grossesteste's scholarly and devotional works, an outline biography, links and bibliography.